sheets



0. A. KENYON. METHOD OF SERIES ARC WELDING.

APPLICATION FILED JAN-9,1918.

Patented May 13, 1919.

- 2 SHEETS-SHEET 1.

JWMM M '0. A. KENYON. 7 METHOD OF SERIES ARC wuome.

APPLICATION FILED JAN. 9. 1918.

Patnted May 13, 191% L8A1 d,

Inventor.

orrs ALLEN KENYON, onnnw YonK, 1v. Y.

METHOD or sn'mns Ans-WELDI G.

Application filed January 9, 1918. Serial No. 211,081.

To all whom it may concern:

Be it known; that I, .O'rrs A. KENYoN, a

" citizen of the=United States, residing at New York city, iii-the county of New Yorkand (is a specification.

' steps and the process resultin 'State of New York, haveinv'ented certain .new and useful Improvements in Methods of Series Arc-Welding, of which the following My invention relates to a method of series arc welding, and the same consists of the substantially as I will 'hereina ter describe and claim. J

In the accompanying drawings I have illustrated various apparatus by which the present process may be carried out and wherein- Y I Figure 1 is a diagram showing the application of subdivided line resistances to' a series arc welding system.

Fig. 2 illustrates the interior connection of one .ofthe are controllers, C.

Fig. 3 illustrates internal connections for a controller which does not involve automatic means of removing a resistor from the line circuit after the arc has been extinguished. I Fig. 4 illustrates another method of connecting the controller. v

Fig. 5 illustrates an arrangement wherein only one contactor is employed.

Fig. 6 is an enlarged part elevation and part sectional view of the contactor l of Fig.

l showing its coils 8 and 11.

Fig. 7 is an enlarged part elevation and ,part sectional View of the contactor of Figs.

2, 3 and 5 showing a single'coil 72 'While the drawings show desirable em bodiments of apparatus-for carrying out the process I am about to describe, it will be understood that the-process is not limited to these particulanarrangements and that it .compre'hends andincludes any mechanism or arrangement of parts which will produce the desired results. 7

In connection with theseries arc welding system describedand claimed in my prior Patent Number 1,181,227, dated May 2, 1916,

it is often found desirable to connect a resistance 1n the mam line on account of the fact that the line resistance itself is not sufiicient to absorb shocks, due to sudden changes in load voltage and this allows momentary swings in' the current which. interfere with other welders on the line. To overcome this objection I have devised a method which Specification Letters Patent.

therefrom,

Patented May 13, 1919.

comprehendsthe use of a resistance per- .ma'nently connected in-the line, the function of said resistance being, essentially, to dampen current fluctuations by absorbing energy. While this resistance as compared with the resistance required by constant potential systems is negligible, nevertheless, it

is highly desirable to be able to reduce it to a minimum, and accordingly in my present some instances a moment later be removed from the circuit automatically.

Referring to the accompanying drawings for a better understanding of the invention In Figs. 1 and 2 I illustrate the application of my subdivided line resistance to a series arc welding system such as is covered by the aforesaid prior patent.

Fig. 1 shows diagrammatically the series arc welding system operated by a self-regulating motor-generator set, wherein M represents the motor; G the generator; R the regulator; R the permanent line resistance;

C the arc controller; and Atlas welding arc.

Ihe constructions and general arrangements of thesecontrollers may be of the usual or any desired form, but in Fig. 2, I show the internal connection of an arc controller, C,

which will be found very useful in the carrying out of my invention. In this figure, 1 and 2 are the line conductors; 3 and 4 are contactors;'5 and 6 are resistors; 7, 8, 10 and 11 are coils; 9 is a rheostat; 12, is an external source of excitation; 13 is a contactor; 14L

isa circuit closeror pushbutton; and 15 and 16 are springs connected to the contactors.

3 and 4:. v v

In this arrangement, the hue comes 1n at 1. Normally, the contaotors 3.and 13 are closed and the. circuit closer or push button 14 is open so that under those conditions the current beginning at 1, passes directly through the conductors to the contactor 13,

and fromthere it passes to the conductor, 2.

When the Welder is already to begin operation, he closes the circuit by pressing the button, 14, which short circuits the winding or coil, 11, known as the holding coil, and this opens the contactor, 13.. Now,-the circuit is made through the contactor, 3, and the resistor, 5, to the line 2, and across the terminals of the are, A, where we have a voltage equivalent to the drop in the resistor, 5. The operation of bringing the terminals of the are together preparatory to starting an arc, will now draw current through the coil, 7, which opens the contactor, 3, against the pull of its spring, 15, thereby leaving the are as the only circuit in series with the line. Under these conditions, the current continues to pass through the are as long as the length of said are does not exceed. a predetermined amount. I

It will also be noted that across the arc is connected the coil, 8, which is inseries with the rheostat, 9, and when the arc voltage, which is a measure of the length of the arc, reaches a predetermined value, sufficient current will pass through the coil, 8, to close the contactor, 4, against the pull of its spring, 16, thereby inserting the resistor,

6, which is one of the subdivisions of the line before referred to, and in this way killing the are, which will send a main line current through the resistor, 6. This resistor being included between the terminals of the coil, 8, will cause enough current to be sent through said coil to hold the contactor, 4,

in the closed position.

Across the resistor, 6,

send sufiicient current through the coil, 10,

to close the contactor, 13, and this will short circuit the resistor, 6, and hold the coil, 11, excited from the external source, 13; the short circuit will be maintained until the welder is again ready to start, by pressing the button, 14. The contactor, 3, is closed at the same moment that current ceased in the arc circuit, because extinguishing the are cut ofil' excitation of the coil, 7, and allowed the spring, 15, to close the contactor, 3, thus the system is restored to its original position and is ready to start welding, as above described.

- utilized to maintain In Fig. 3 I show the application of my invention to a controller which does not in volve automatic means of removing the restruck, it short circuits the resistor, 6, and .coil, 8, and allows the contactor, 4,:to open.

It is manifest that the closing of the switch, 10', will accomplish the same purpose.

InFig. 4, I show another method of connecting thecontroller which does not provide automatic means for removing the rep I also have the coil, 10, and the current through said resistor will sistor, 6, from the circuit, after the arc has been extinguished, but in this particular instance, I do not rely upon the drop through the resistor to hold the contactor, 4, in the closed position. For this last namedpurpose, in the instance noted, I utilize the holding coil,-11, excited from its source, 12, the switch being released by the push button, 14, when-it is desired to begin welding.

Referring again to Fig. 2, the cycles of operation are substantially as follows: 3

I begin with practically no voltage between the terminals, 1 and 2, and by dropping out the contactor, 13, I insert the resistance,', .5, which gives a voltage approximately equal to. the normal are. The striking of the arc does not change this voltage appreciably, but the drawing out of the are to a maximum predetermined length, raises the voltage gradually, and when the predetermined value is reached, it is dropped suddenly to that corresponding to the resistance, 6, and a moment later it is dropped back to zero by short circuiting said resistance. Formerly, when the predetermined voltage was reached, this being the maximum load across the arc, the closing of the contactor, 4, short circuited the panel completely, thereby making a comparatively large and very sudden change in voltage.

In the construction found in Fig. 3, the operation is substantially as follows:

The contactors, 3 and 4, are assumed to be closed at the beginning of the operation. Touching the arc to the work short circuits the coil, 8, and this allows the contactor, 4, to open; practically speaking, the contactors, 3 and 4, open simultaneously. As the arc is drawn out, the voltage builds up, sending a proportionate amount of current through the coil, 8. Once the length of the arc reaches the limit fixed by the adjustment of the rheostat, 9, the current through the coil, 8, will become great enough to close the contactor, 4, placing the resistor, '6, in parallel with the are. This resistance being relatively much lower than the are, the offeet is equivalent to short circuiting the are, and thus extinguishes it immediately. As .s'oon as the current in the coil, 7, decreases to a definite amount, the contactor, 3, closes, placing the resistor, 5, in parallel with the resistor, 6, thus reducing the resistance in series with the line and therewith the loss. The system is thus restored to its normal condition and is ready to start again.

The operation of the device shown in Fig. 4 is practically the same as that described for Fig. 3, except that the arc is started by releasing the contactor, 4, by means of the push button, 14, which short circuits the holding coil, 11. In both Figs. 3 and 4, the arc voltage rises to the upper limit, drops to a lower value fixed by the resistor, 6, and then to a still lower value. fixed by resistance, 5, in parallel with resistor, 6.] In Fig. 5 I show an arrangement employin only one contactor and in this instance the v rin ing of the welding electrode in contact wit the work, short circuits the coil, 8, whereupon the arc branch is placed in series with the line and carries the line current. In this "condition, the arc may be built up to the limit set by 'therheostat in series with the coil, 8. When this limit is reached the coil, 8, closes-the contactor, 4, placing the relatively low resistance, '6, in parallel with the are which extinguishes it immediately, leaving the resistor alone in series with the In Figs. 6 and 7, I illustrate a more or less detailed construction of the contactors 3 and 4 in order that the foregoing de-' scription may be better understood. The contactor 4:, of Fig. 6, has, preferably two coils 8 and 11, corresponding to the showing of Fig. 4; the contactor of Fig. 7, has

" a single coil 7 similar to the showing in l i s. 2, 3 and 5.

ing in dividing the main line into-sections each having awelding are, striking an are and drawing it out to a predetermined volt.- age limit, en shunting the arc and dropplng the voltage of its section to a point be low the arc voltage limit, and then shortcircuiting said section.

3. A method of series arc welding consisting in dividingthe main line into sections each having a welding are, striking an arc and drawing it out to a predetermined voltage limit,'t en shunting the arc and dropping thevoltage of its section to a point] be-,

low the arc voltage limit, then further reducing the volta e in said section.

4. method 0 series arc welding consisting in dividing'the main line intosectionsv each having a welding arc, striking an arc and drawing it outto a predetermined voltage limit, t en shunting the are and droppihg the voltage of its section to a point below the arc voltage limit, then further reducingthe voltage in said section, and then short-circuiting the said section.

5. A method of series arc welding consisting 1n dividing the main line into sections each having a welding arc, striking an arc and drawin it out to a predetermined voltage limit, tien shunting the arc and dropglng the voltage of its section to a point elow the arc voltage limit, then gradually lessening the voltage in saidsection to zero.

6. A method of series arc welding consisting in dividing the main line into sections each having a welding arc, dividing the artificial line resistance into portions corresponding in number to the said sections, insertin in each section its portion of the artific al resistance, then drop ing from the linethe inserted resistance w ile its corre-' sponding'arc is in operation. l

7. A method of series are weldlng conslsting in dividing the main line into sections each having a welding arc, raisin the voltage in a section, then striking t e are of said section, then drawmggout the arc to a predetermined voltage limit, then shunting Y section below the arc voltage'limit, and then dropping the voltage back to zero.

8. A method of series arc welding consistthe arc and dropping the voltage in said ing individing the main line into sections 7 each having a welding arc,'raising the voltage in a section to equal approximately normal arc voltage, then strikmg the are in sa1d section, then drawing out the arc to a predetermined voltage limit, then shunting the arc and dropping the voltage in sai section below the arc voltage limit, and then dropping the voltage back to zero. v

9. Amethod of series-arc welding consisting in dividing themain line intosections each having a welding arc, inserting a resistance into a section, then striking the are of said section and removing said resistance, then drawing out the arc to a predetermined voltage limit, then shunting sa1d arc with resistance, and then reducing the resistance;

of said shunt.- In testimony whereof I afiix my signature.

OTIS ALLEN KENYON. 

